Computer Models and Simulations

1. When customers visit a supermarket, they do not expect to wait in checkout queues for too long, however the supermarket manager cannot afford to have all the checkouts open all of the time.

In an attempt to solve the problem the supermarket manager may decide to make a computer model using a spreadsheet to calculate the optimum number of checkouts that should be open at any time. N07P1

(a) Define the term computer model. (2)

A computer model is a computer program that utilizes mathematical data and trends to represent a real-world situation. It is used to demonstrate larger items or larger problems, and to simplify them in order to gain a better understanding of the problem or object through a mathematical equation.

(b) Describe two inputs into the model that would be needed in order to calculate the best number of checkout operators. (4)

One input that would be needed to calculate the best number of checkout operators would be the salary of a checkout worker per hour, determining how much a checkout operator makes in an hour, while the second input needed would be the sales per hour for the store in question, to determine when peak sales are, and to calculate what the most profitable amount of checkout operators would be for every hour the store was open. This way the store would be able to employ the right amount of checkout workers to achieve the greatest amount of profits for every hour the store is open, and would maximize thier profits.

(c) Explain why this or any other computer model may not give accurate results. (4)

This may not give accurate results, because there are other factors that may not be included into the computer model. For example, in the above model, there are other factors that are ignored. For example the sales per hour may not stay consistent. On Monday the peak sales may occur at 4pm while on Thursday they could occur around 11am. This inconsistency may endanger the plan, although it could be avoided if there is a different schedule for every day of the week. Also, there is the additional factor of the holidays; sales patterns differ around the holidays, something that was also not taken into account by the model. The most common reason that a computer model may not give accurate results is the exclusion of factors, as happened above. Also, computer models may give inacccurate results because they received inaccurate data, which prevented them from accurately modeling whatever they are modeling.

2. Computer models and computer simulations are often used by businesses to test and train staff. One situation where a computer simulation is used is in the training of airline pilots. M07P1

(a) Define the term computer simulation. (2)

The term computer simulation refers to a computer program that utilizes mathematical models and other computer models to visually simulate reactions and events in the real world. It creates a visual representation of a real world situation in order to allow people to study or interact with the simulation, allowing people to gain knowledge of natural processes or train pilots to fly before actually letting them fly an actual plane.

(b) Describe two input devices that would be used in a pilot training computer simulation. (4)

One input device that would be used in a pilot training simulation would be a yoke, in order to allow the pilot to interact realistically with the computer model as if it were an actual plane, and to indicate the direction and heading the aircraft in the simulation will follow. This allows a realistic interaction between the pilot and the simulation, making it seem like an actual flight. A second input device that would be used in a pilot training would be the airspeed and rudder controls for the aircraft. This would allow the pilot to control the airspeed and flaps of the plane, as he would do so in a real life situation, only this time he was doing so with an simulator, in order to train for the real thing, and gain the necessary experience before ever having to actually go and fly the plane.

(c) Explain one benefit and one problem associated with training pilots on simulators instead of using real planes. (4)

One benefit to training pilots on simulators instead of on planes is the fact that there would be no risk to the pilots if they made a mistake. They wouldn't crash. There was no risk to them. And there was no loss of the actual plane, and therefore no subsequent risk of the loss of investment. The pilot is able to learn in an entirely risk free manner and in a trial and error, and can discover the nuances to flying in an easier environment. A drawback to training pilots on simulators as opposed to the real thing is the fact that there are factors you can't foresee that would be helpful to the pilot to experience. Also, the simulator cannot replicate the feel of flying, and may fail to adequately prepare the pilot for flight by himself.